/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.tools.javac.processing;

import javax.annotation.processing.Messager;
import javax.lang.model.element.AnnotationMirror;
import javax.lang.model.element.AnnotationValue;
import javax.lang.model.element.Element;
import javax.tools.Diagnostic;
import javax.tools.JavaFileObject;

import com.sun.tools.javac.model.JavacElements;
import com.sun.tools.javac.tree.JCTree;
import com.sun.tools.javac.tree.JCTree.JCCompilationUnit;
import com.sun.tools.javac.util.Context;
import com.sun.tools.javac.util.JCDiagnostic;
import com.sun.tools.javac.util.Log;
import com.sun.tools.javac.util.Pair;

/**
 * An implementation of the Messager built on top of log.
 * 
 * <p>
 * <b>This is NOT part of any supported API. If you write code that depends on
 * this, you do so at your own risk. This code and its internal interfaces are
 * subject to change or deletion without notice.</b>
 */
public class JavacMessager implements Messager {
	Log log;
	JavacProcessingEnvironment processingEnv;
	int errorCount = 0;

	JavacMessager(Context context, JavacProcessingEnvironment processingEnv) {
		log = Log.instance(context);
		this.processingEnv = processingEnv;
	}

	// processingEnv.getElementUtils()

	public void printMessage(Diagnostic.Kind kind, CharSequence msg) {
		printMessage(kind, msg, null, null, null);
	}

	public void printMessage(Diagnostic.Kind kind, CharSequence msg, Element e) {
		printMessage(kind, msg, e, null, null);
	}

	/**
	 * Prints a message of the specified kind at the location of the annotation
	 * mirror of the annotated element.
	 * 
	 * @param kind
	 *            the kind of message
	 * @param msg
	 *            the message, or an empty string if none
	 * @param e
	 *            the annotated element
	 * @param a
	 *            the annotation to use as a position hint
	 */
	public void printMessage(Diagnostic.Kind kind, CharSequence msg, Element e,
			AnnotationMirror a) {
		printMessage(kind, msg, e, a, null);
	}

	/**
	 * Prints a message of the specified kind at the location of the annotation
	 * value inside the annotation mirror of the annotated element.
	 * 
	 * @param kind
	 *            the kind of message
	 * @param msg
	 *            the message, or an empty string if none
	 * @param e
	 *            the annotated element
	 * @param a
	 *            the annotation containing the annotaiton value
	 * @param v
	 *            the annotation value to use as a position hint
	 */
	public void printMessage(Diagnostic.Kind kind, CharSequence msg, Element e,
			AnnotationMirror a, AnnotationValue v) {
		JavaFileObject oldSource = null;
		JavaFileObject newSource = null;
		JCDiagnostic.DiagnosticPosition pos = null;
		JavacElements elemUtils = processingEnv.getElementUtils();
		Pair<JCTree, JCCompilationUnit> treeTop = elemUtils.getTreeAndTopLevel(
				e, a, v);
		if (treeTop != null) {
			newSource = treeTop.snd.sourcefile;
			if (newSource != null) {
				oldSource = log.useSource(newSource);
				pos = treeTop.fst.pos();
			}
		}
		try {
			switch (kind) {
			case ERROR:
				errorCount++;
				boolean prev = log.multipleErrors;
				log.multipleErrors = true;
				try {
					log.error(pos, "proc.messager", msg.toString());
				} finally {
					log.multipleErrors = prev;
				}
				break;

			case WARNING:
				log.warning(pos, "proc.messager", msg.toString());
				break;

			case MANDATORY_WARNING:
				log.mandatoryWarning(pos, "proc.messager", msg.toString());
				break;

			default:
				log.note(pos, "proc.messager", msg.toString());
				break;
			}
		} finally {
			if (oldSource != null)
				log.useSource(oldSource);
		}
	}

	/**
	 * Prints an error message. Equivalent to {@code printError(null, msg)}.
	 * 
	 * @param msg
	 *            the message, or an empty string if none
	 */
	public void printError(String msg) {
		printMessage(Diagnostic.Kind.ERROR, msg);
	}

	/**
	 * Prints a warning message. Equivalent to {@code printWarning(null, msg)}.
	 * 
	 * @param msg
	 *            the message, or an empty string if none
	 */
	public void printWarning(String msg) {
		printMessage(Diagnostic.Kind.WARNING, msg);
	}

	/**
	 * Prints a notice.
	 * 
	 * @param msg
	 *            the message, or an empty string if none
	 */
	public void printNotice(String msg) {
		printMessage(Diagnostic.Kind.NOTE, msg);
	}

	public boolean errorRaised() {
		return errorCount > 0;
	}

	public int errorCount() {
		return errorCount;
	}

	public void newRound(Context context) {
		log = Log.instance(context);
		errorCount = 0;
	}

	public String toString() {
		return "javac Messager";
	}
}
